Third to alex



PATENT OFFICE.

MARK W. MARSDEN, OF PITTSBURG,

PENNSYLVANIA, ASSIGNOR OF ONE- THIRD TO ALEX. MATQ JHE'I'T, OF SAMEPLACE.

PLASTERING COMPOUND.

SPECIFICATION forming part of Letters Patent No. 269,219, dated December19, 1882.

Application filed October 13, 1882. (No specimens.)

To all whom it may concern:

Be it known that 1, MARK W. ll/IARSDEN, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, lJaXB invented a new and use- 5 fulImprovement in Plastering Compounds; and I do hereby declare thefollowing to be a full, clear, and exact description thereof.

My invention is directed to the production of a plaster or plasteringcompound which 10 will be more adhesive, more elastic, warmer, tougher,lighter, and cheaper than ordinary plaster, and whichca-n be used overagain. I obtain such a plaster by a composition of paper or wood pulp,clay or mineral powder, and

I5 paste or sizing. The paper or wood pulp is the same as that used bypaper-manufacturers in the manufacture of paper or of strawboard. Forordinary plastering the vegetable pulp is of the cheapest kind. Themineral pow- 2o der used is made of soapstone, terra-alba, or

other suitable clay. The paste or sizing used are of the cheaper kindsused by paper-hangers, calciminers, and whitewashers. For finer work thebetter and more expensive varieties ot'these 2 5 materials are used.

I can make my improved plaster either for hard or forsoft, pliable, orelastic walls. For hard walls I prefer to use the following or about thefollowing proportions, viz: vegeta- 0 ble pulp, one-third; mineralpowder, one-half; Y sizing,one-sixth. Theseingredients are placedtogether in a box and mixed with sufiicient water to give them theconsistency of mortar. It is then applied to the wall in the usual way.5 For soft or elastic walls I usethe following or about the followingproportions, viz: vegetable pulp, three-fourths mineral powder,oneeighth; sizing, one-eighth. If it is desired to render the wallfire-proof, I add a small per- 0 centage of common salt or equivalentsub- |stancessuch as soda or pearlash-which,

when exposed to the heat caused by a fire or against the wall, willproduce an extinguishing-gas. Coloring-matter may also be added if it isdesired to color or tint the wall. The vegetable pulp which I prefer touse is dry wood pulp, because it mixes up better and smoother than otherpulps, and is of a fine adhesive body. The mineral powder gives body tothe mass and acts as a hardener.

The advantages of my improved plaster are that it is cheaper than theordinary plaster, as it does not require to be laid on the wall sothick. It is warmer, because it is a better non-conductor. It is morehealthful, because no animal hair is used in its composition. It is moretenacious,and,beingofahomogeneous,fibrous,

by grinding it up it can be used over again.

1 am aware that it has been proposed to use vegetable fiber inconnection with lime, putty, and other ingredients in the manufacture ofnon conducting boiler coverings, tire brick, roofing-tile, and similaruses, and I make no claim for any such things; but

What I do claim isl 1. A plastering compound for the walls and ceilingsofhouses, composed of vegetable pulp, mineral powder, and sizing,substantially as and for the purposes described.

'2. A plaster composed of vegetable pulp, mineral powder, sizing, andsalt, substantially as and for the purposes described.

In testimony whereof I have hereunto set my hand this 5th day ofOctober, A. D. 1882.

MARK W. MARSDEN.

Witnesses:

T. B. KERR, J. K. SMITH.

tough structure, will not chip or scale ofifand

